Trisazo dyestuffs



Patented Nov. 14, 1944 5 UNITED STATES PATENT 2,362,548 FFICE f TRISAZO DYESTUFFS Joseph Gyr andRaymond Gunst, Basel, Switzerland,assignors to Society of Ghemical Industry in Basle, Basel, Switzerland, a Swiss company No Drawing. Applicationjune 15, 1942, Serial No. 447,148. In Switzerland July 5, 1941 3 Claims. (01. 260-169) which the NH2 and the -N=N groups are in In British Patent No. 20,278/97, trisazo dyestufis are described which correspond to the general formula on v on in which R1 represents an arylene nucleus, for example, a phenylene or a diphenylene nucleus, in which the two azo groups are placed in the 1:4- or 4:4'-position to one another, and in which R2 stands for the radical of a hydroxynaphthalene sulfonic acid, in which the azo group united to the radical R1 is connected to the position in the naphthalene nucleus ortho to the OH-group and in which the other azo group is linked to the other portion ofthe naphthalene nucleus.

From British Patent No. 523,918 it is further to be inferred that, among the above dyestufis, those in which the radical R2 is derived from 2 amino-5 hydroxynaphthalene 'i sulfonic acid in which R represents an arylene radical of the benzene series, in which the two azo groups stand in the 1:4-position to one another, and in which the two a: represent hydroxyl or amino groups.

These dyestuffs are most simply prepared by the 1:4-position to one another, and coupling them with 2 molecules of resorcinol or 2 molecules of meta-aminophenol or 1 molecule resorcinol and 1 molecule meta-aminophenol.

The following examples illustrate the invention, but are not to be regarded as limiting it in any way,-the parts being by weight:

, Example 1 15.0parts of 1-amino-4-acetaminobenzene are diazotized in known manner and are coupled with a solution of 23.9 parts of 1-amino-5-hydroxynaphthalene-7-sulfonic acid made alkaline .I with soda The coupling is complete after stirring has been continued for several hours. The mixture which, amounts to about 800, parts by volume is heated to 90 C., and the acetamino group is saponified by addition of 110 parts of caustic soda solution of 30 per cent. strength, and further heating to 90-100 C. for about 1% hours. Byaddition of common salt, the diaminoazo dyestuff, 4'- amin0benzene-(1-azo-2) -5'-amino-1'- hydroxynaphthalene sulfonic acid-3 is precipitated and is filtered whilst hot. The sodium salt of the dyestufi is again stirred in about 1000 parts of water, a solution of 13.8 parts of sodium nitrite is added and tetrazotization is brought about by addition of 55 parts of hydrochloricacid of. 30 per cent. strength at 15 C The tetrazo compound is coupled with a solution tetrazotizing azo dyestuffs of the general formula , x NH:

. 6H in which R stands for a phenylene radical. in

of 22 parts of 1:3-dihydroxybenzene made alkaline with soda. After stirring for several hours coupling is complete, andthe dyestufi, which is mostly precipitated, can be filtered directly. It corresponds in the free state to the formula j HOxS Ho-QNm-Ormv The new fdyestuff is a very bronzy powder whichdissolves in water to a violet and in concentrated sulfuric acid to apure blue solution. It dyes'cotton in violet-black shades by aftertreatment with 1-diazo-4-nitrobenzene on the fibre, olive-black shades which are very fast to washing are obtained.

Replacement of resorcinol by 21.8 parts of V meta-aminophenol leads to a product which pos- It correspondsin the sesses similar properties. free state to the formula nms NH: HOQN=NON=N and dyes cotton violet black shades which, by after-treatment with =1-diazo-4.-nitrobenzene, be come essentially blacker.

The same dyestufi is obtained if the 1-amino- 10 parts of sodium nitrite and neutralized with 10 parts of soda-and 20 parts of sodium acetate. The material is worked for. /2 hour therein and is then thoroughly rinsed. A deep olive-black dye- 4-acetaminobenzene be replaced by the corre-",- 1; ing is obtained of very good fastness to water and sponding oXamic acid derivative, or also by 1.-

diazo--nitrobenzene, the nitro group of the azo dyestuff then being converted into an amino group by treatment with reducing agents after:v

the first coupling has taken place.

Similar dyestuffs are obtained if the l-aminol-acetaminobenzene be replaced by;its'nuc1ear substituted products, for example, by 1-amino-2-' chloro 5 methoxy-4-acetaminobenzene 'or' 1'-..

washing which yields excellent discharges with both neutral and alkaline discharge colors.

-Whatweclaim is:

pL'The mono'sulfonated azo dyestuffs corresponding in the free state to the general formula in which R represents an arylene radical of the Dyeing de- Direct dyeing velopedwith Tetrazotized monoazo dyestufi I F rst component 7 Second component on cotton 1418264 nitrobenzene No. l4-amino-2:5 dimethylbenzene(1-azo-2)*5- 1:3-dihydxoxy-benzene 1:3-dihydroxy-benzene .l Grey Olive black.

amin0-1-hydroxynaphthalene'sulfonic acid-3. i N -24-amino-2:E-dichlorobenzene-(l-azo-2)-5- ..1dcm idem Violet black... Idem. ami o-1-hydroxynaphthalene-sulionic acid-3. N ,3 4-amino-3-methoxybenzene-(1-az0-2)-5- 1dem .1dem Blue,b1ack.. Black olive. amin l-hydroxynaphthalene-sulionic acid-3; 1 1 4 Idem 1-hydroxy-3-emmo-benzene. 1-hydroxy-3-ammo benzene V1oletbiack Black. 5-4-amino-2:5-dimethoxybenzene 1-azo-2)- lc3-diliydroxy-benzene l:3-d1hydroxy-be nzene Blue green.- Olive green.

sh -1'-hydroxynaphthalene sulfonic acid- I N0 4. i -2-chloro-5-methoxybenzene-(l- -..ide -.1 em Blue black Black olive.

azo-2')-5'-amlHO-1'-]1ydIOXY11&phtha1el16 sula tonic acid-3- 7 Idem l-hydroxy-3-am1n0-benzene l-hydroxy-il-amino-benzene. do Olive black.

The dyestuffsNos. 2, and 6 correspond in th freeform to the following formulas: v

A dyebath is prepared by adding 1 part of the dyestuff described in paragraph 1 oi-Example 1.

1 part of anhydrous sodium carbonate and parts of sodium sulfate in 1000 parts of water. 50 parts of cotton are entered therein at,40.-50- C., the bath is brought gradually tov the boil and boiling is continued for about-1 hour. The rna- 65 terial is-then rinsed. I V I The cotton which ha sgbeen dyed ina violet a s ed i w. n ered af r n d benzene series, in which the two azo groups stand in the 124-po'sition to each other and in which each of the'two .70 represents a substituent selected from the group consisting of hydroxyl and amino groups. I e 1 I I 2. The monosulfonated azo dyestuffs corresponding in the free state to the general formula I- I=N OH I Hols in which R represents an arylene radical of the benzene series and in which the twoazo groups stand in the 1:4 -position.to-each other.

3. The monosulfonated azo dyestufi' corresponding inthe free state to the formula N=N on HOaS .7 I H 7 JOSEPH GYR.

RAYMOND GUNST. 

